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CSAMT在松辽盆地梅里斯地区铀矿勘查中的应用

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世界核地质科学 2024年第1期41卷 174-184页

作者：牛禹王培建张正阳谢明宏核工业航测遥感中心河北石家庄050002 中核集团铀资源地球物理勘查中心(重点实验室) 河北石家庄050002 河北航空探测和遥感技术重点实验室河北石家庄050002

上白垩统四方台组是松辽盆地北部铀矿找矿的主要层位之一,其铀矿化主要受控于上白垩纪曲流河三角洲沉积体系,工业铀矿体主要在底部砂岩层富集,多呈板状、透镜状,矿体规模与砂体规模、层数等密切相关,砂体规模越大,矿化层越多,矿体规模越... 详细信息

上白垩统四方台组是松辽盆地北部铀矿找矿的主要层位之一,其铀矿化主要受控于上白垩纪曲流河三角洲沉积体系,工业铀矿体主要在底部砂岩层富集,多呈板状、透镜状,矿体规模与砂体规模、层数等密切相关,砂体规模越大,矿化层越多,矿体规模越大,反之则规模越小。但是上白垩统四方台组底部砂体在松辽盆地西部超覆带内梅里斯地区发育情况尚不明确。以可控源音频大地电磁测深(CSAMT)为手段,利用Occam算法反演得到研究区电阻率断面,结合研究区内各地层岩石电阻率特征,分析了研究区内盖层结构,尤其是找矿目的层上白垩统四方台组的空间分布特征,同时还推断了基底起伏特征以及断裂走向、倾向及其延深情况。研究结果显示:研究区内四方台组河流相砂体主要分布于研究区的东南部,多呈透镜状,整体表现为自南东向北西呈逐渐尖灭的特征,厚度一般不超过180 m。研究成果为钻探工程的部署提供了依据。

关键词：可控源音频大地电磁测深四方台组松辽盆地砂体

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高铁高硫铝土矿氧压提质脱硫降铁研究

有色金属（冶炼部分） 2024年第10期 119-127页

作者：张正阳王海北杨玮娇杨永强韦其晋彭煜华王伟矿冶科技集团有限公司北京100160

高铁高硫铝土矿的提质利用对于保障我国铝工业战略矿产资源安全具有重要意义。针对含铁13.66%、硫16.24%的一水硬铝石型高铁高硫铝土矿,主要铁、硫物相为黄铁矿,绘制了Fe-S-H2O系电位-pH图。结果表明,当体系pH小于Fe3+水解临界pH时,能... 详细信息

高铁高硫铝土矿的提质利用对于保障我国铝工业战略矿产资源安全具有重要意义。针对含铁13.66%、硫16.24%的一水硬铝石型高铁高硫铝土矿,主要铁、硫物相为黄铁矿,绘制了Fe-S-H2O系电位-pH图。结果表明,当体系pH小于Fe3+水解临界pH时,能够实现铁、硫的同步浸出。采用加压浸出法处理,在液固比4 mL/g、浸出温度170℃、氧气分压0.20 MPa、保温时间2 h条件下,铁、硫浸出率分别为94.08%和98.34%,浸出渣铁、硫含量分别为1.23%和0.41%,XRD结果表明,浸出渣物相主要为一水硬铝石,实现了高铁高硫铝土矿的提质。浸出液主要溶质为硫酸铁,具有铁、硫进一步资源化利用的潜力。

关键词：高铁高硫铝土矿提质利用加压浸出 Fe-S-H2O系

High-frequency enhanced response based on Sb_(2)Te_(3)topological insulators

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Photonics Research 2022年第10期10卷 2302-2308页

作者： SHI zhang CHAOFAN SHI WEIWEI TANG LIBO zhang LI HAN CHENGSEN YANG zhengyang zhang JIAN WANG MIAO CAI GUANHAI LI CHANGLONG LIU LIN WANG XIAOSHUANG CHEN WEI LU College of Physics and Optoelectronic Engineering Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China State Key Laboratory of Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China Department of Optoelectronic Science and Engineering Donghua UniversityShanghai 201620China Terahertz Technology Innovation Research Institute Shanghai Key Laboratory of Modern Optical SystemUniversity of Shanghai for Science and TechnologyShanghai 200093China

Topological insulators represent a new quantum phase of matter with spin-polarized surface states that are protected from backscattering, exhibiting electronic responses to light, such as topological quantum phase transitions. However, the effects of high-frequency driving topological intrinsic systems have remained largely unexplored challenges experimentally for high-sensitivity terahertz detection. In this study, by integrating Sb2Te3 topological insulators with subwavelength metal antennas through micro-nano processing, a high-frequency terahertz detector with high sensitivity is proposed. The enhanced response originates from the asymmetric scattering of the surface electrons in the Sb_(2)Te_(3) flakes induced by the terahertz wave. The device displays room-temperature photodetection with a responsivity of 192 mA/W and equivalent noise power of less than 0.35 nW/Hz^(1/2) in the frequency range from 0.02 to 0.3 THz. These results pave the way for the exploitation of topological insulators for high-frequency operation in real-time imaging within long-wavelength optoelectronics.

关键词： scattering insulator quantum

Super-resolution diffractive neural network for alloptical direction of arrival estimation beyond diffraction limits

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Light(Science & Applications) 2024年第8期13卷 1602-1614页

作者： Sheng Gao Hang Chen Yichen Wang zhengyang Duan Haiou zhang Zhi Sun Yuan Shen Xing Lin Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China

Wireless sensing of the wave propagation direction from radio sources lays the foundation for communication,radar,navigation,***,the existing signal processing paradigm for the direction of arrival estimation requires the radio frequency electronic circuit to demodulate and sample the multichannel baseband signals followed by a complicated computing process,which places the fundamental limit on its sensing speed and energy ***,we propose the super-resolution diffractive neural networks(S-DNN)to process electromagnetic(EM)waves directly for the DOA estimation at the speed of *** multilayer meta-structures of S-DNN generate super-oscillatory angular responses in local angular regions that can perform the all-optical DOA estimation with angular resolutions beyond the diffraction *** spatial-temporal multiplexing of passive and reconfigurable S-DNNs is utilized to achieve high-resolution DOA estimation over a wide field of *** S-DNN is validated for the DOA estimation of multiple radio sources over 5 GHz frequency bandwidth with estimation latency over two to four orders of magnitude lower than the state-of-the-art commercial devices in *** results achieve the angular resolution over an order of magnitude,experimentally demonstrated with four times,higher than diffraction-limited *** also apply S-DNN’s edge computing capability,assisted by reconfigurable intelligent surfaces,for extremely low-latency integrated sensing and communication with low power *** work is a significant step towards utilizing photonic computing processors to facilitate various wireless sensing and communication tasks with advantages in both computing paradigms and performance over electronic computing.

关键词： beyond optical network

Design of bionic water jet thruster with double-chamber driven by electromagnetic force

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International Journal of Mechanical System Dynamics 2024年第3期4卷 292-302页

作者： Chong Cao Yasong zhang Chengchun zhang Chun Shen Wen Cheng Zhenjiang Wei zhengyang Wu Luquan Ren Key Laboratory of Bionic Engineering(Ministry of Education) Jilin UniversityChangchunChina Weihai Junming Power Technology Co.Ltd. WeihaiChina

In response to the limitations of the single-chamber water jet thruster used in underwater vehicles mimicked by natural cephalopods,a novel approach involving a double-chamber water jet thruster has been *** thruster utilizes electromagnetic force to manipulate the diaphragm,thereby altering the volume of the upper and lower chambers to achieve water jet *** investigations were conducted to determine the tensile length-force characteristics of the diaphragm made of ***,key parameters of essential propulsion components,such as solenoid coils,electromagnets,and currents,were established based on the tensile length-force curve,and the propulsion capabilities of the system were evaluated through theoretical *** assessments indicate that the system does not produce reverse thrust regardless of whether the coil moves up or *** experimental results demonstrate that the maximum peak propulsion force generated by the dual-chamber water jet thruster within a 3-s cycle is 0.253N.

关键词： water jet thruster diaphragm electromagnetic force

Research on the design method for uniform wear of shield cutters in sand-pebble strata

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Deep Underground Science and Engineering 2024年第2期3卷 216-230页

作者： Jinxun zhang Bo Li Guihe Wang Yusheng Jiang Hua Jiang Minglun Yin zhengyang Sun Beijing Urban Construction Group Co. Ltd.BeijingChina China University of Geosciences BeijingChina China University of Mining and Technology BeijingChina

During shield tunneling in highly abrasive formations such as sand–pebble strata,nonuniform wear of shield cutters is inevitable due to the different cutting *** downtimes and cutter replacements have become major obstacles to long-distance shield driving in sand–pebble *** on the cutter wear characteristics in sand–pebble strata in Beijing,a design methodology for the cutterhead and cutters was established in this study to achieve uniform wear of all cutters by the principle of frictional *** applicability of the design method was verified through three-dimensional simulations using the engineering discrete element *** results show that uniform wear of all cutters on the cutterhead could be achieved by installing different numbers of cutters on each trajectory radius and designing a curved spoke with a certain arch height according to the shield *** the uniform wear scheme,the cutter wear coefficient is greatly reduced,and the largest shield driving distance is increased by approximately 47%over the engineering *** research results indicate that the problem of nonuniform cutter wear in shield excavation could be overcome,thereby providing guiding significance for theoretical innovation and construction of long-distance shield excavation in highly abrasive strata.

关键词： cutter wear EDEM model long-distance shield driving sand-pebble stratum shield tunnel uniform wear design method

Multi-field Split Curvature Wavefront Sensing and its Application in the Large Field Survey Telescope

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Research in Astronomy and Astrophysics 2024年第8期24卷 60-74页

作者： Zhixu Wu Yiming zhang Jianan Cong Hua Bai Yong Xia Rongxin Tang Ming Li zhengyang Li Xiangyan Yuan Institute of Space Science and Technology Nanchang UniversityNanchang 330031China Nanjing Institute of Astronomical Optics&Technology CASNanjing 210042China University of Chinese Academy of Sciences NanjingNanjing 211135China

The image quality of a large field survey telescope with a fast focal ratio of the primary mirror is high sensitivity to the optical elements’misalignments and the primary mirror’s *** maintain good optical performance,the perturbations need to be aligned,and the tomographic reconstruction of these perturbations can be derived from wavefront sensing with multi-field points for *** work undertakes a comprehensive examination related to the implementation and optimization of a multi-field split curvature wavefront sensing system,including defocus distance,signal pre-processing,deblending of overlapped doughnuts,field-dependent correction,and distorted coordinate *** also conduct experiments to demonstrate the application and performance of a multi-field split curvature wavefront sensing system in *** the context of the decentering of the secondary mirror,the coefficient of determination(R)attains a high value of 0.993,indicating a robust linearity between the coma coefficients and the decentering of the secondary mirror.A comparative analysis of the simulated and experimental results shows that the difference between them is less than 0.1λ.

关键词： Instrumentation high angular resolution-Techniques photometric-Techniques image processing

Resistance index and browning mechanism of apple peel under high temperature stress

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Horticultural Plant Journal 2024年第2期10卷 305-317页

作者： Hui Wang Shuhui zhang Zidun Wang Dongmei Li Leiyu Yan Yifeng Feng Xiaojie Liu Rongxin Chen Wenmin Fan Lulong Sun zhengyang Zhao College of Horticulture Northwest A&F UniversityYanglingShaanxi 712100China College of Horticultural Science and Engineering Shandong Agricultural University State Key Laboratory of Crop BiologyTai'anShandong 271018China

Apples are one of the most important economic crops *** of global warming and an aggravation of environmental,abnormally high temperatures occur frequently in fruit-growing season and seriously affect normal fruit growth and reduce fruit quality and *** took five-year-old Ruixue’(Qinfu 1×Pink Lady;CNA20151469.1) fruits as test materials,and the ambient temperature during fruit development was *** results showed that during the fruit-growing season,especially during the rapid growth stage (July to August),the maximum daily temperature exceeded 30℃ and lasted for more than 40 *** determine the effects of high temperature stress on the apple fruit resistance,we treated expanding,veraison,and maturity-period fruits at different *** was found that the fruits of the expanding period showed strong resistance to high temperature stress,whereas during veraison and maturity,fruit resistance to high temperature stress decreased,and the fruit peel browning phenotype ***,the content of malonaldehyde (MDA),hydrogen peroxide (H_(2)O_(2)),and superoxide anion (O._(2)^(-)) in the peel gradually increased with increasing *** content of total phenols,flavanol,and flavonoids in the peel decreased substantially at 45℃.Moreover,it was found that polyphenol oxidase gene (MdPPO1) was most sensitive to high temperature stress in ***,transient and stable MdPPO1 overexpression significantly promoted peel *** transgenic materials were more sensitive to high temperatures,and browning was more severe compared to non-genetically modified organism (WT).Stable MdPPO1 knockout calli obtained via clustered regularly interspersed short palindromic repeats (CRISPR/Cas9) gene knockout technology reduced the browning phenotype,and the resultant fruits were not sensitive to the effects of high temperature ***,MdPPO1 expression may be a key factor of high temperature-related changes observed in the browni

关键词： Malus domestica Borkh High temperature stress Peel Browning MdPPO1

Efficacy and safety of PD-1 blockade plus long-course chemoradiotherapy in locally advanced rectal cancer(NECTAR):a multi-center phase 2 study

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1721-1729页

作者： zhengyang Yang Jiale Gao Jianyong Zheng Jiagang Han Ang Li Gang Liu Yi Sun Jie zhang Guangyong Chen Rui Xu Xiao zhang Yishan Liu Zhigang Bai Wei Deng Wei He Hongwei Yao Zhongtao zhang Department of General Surgery Beijing Friendship HospitalCapital Medical UniversityState Key Lab of Digestive HealthNational Clinical Research Center for Digestive DiseasesBeijingChina Department of Gastrointestinal Surgery The First Affiliated Hospital of Air Force Medical UniversityXi'anChina Department of General Surgery Beijing Chaoyang HospitalCapital Medical UniversityBeijingChina Department of General Surgery Beijing Xuanwu HospitalCapital Medical UniversityBeijingChina Department of General Surgery Tianjin Medical University General HospitalTianjinChina Department of Anorectal Tianjin People's HospitalTianjinChina Department of Radiology Beijing Friendship Hospital Capital Medical UniversityBeijingChina Department of Pathology Beijing Friendship HospitalCapital Medical UniversityBeijingChina Department of Thoracic Surgery/Institute of Thoracic Oncology West China HospitalSichuan UniversityChengduChina

Adding PD-1 blockade in the neoadjuvant regimens for locally advanced rectal cancer(LARC)patients with microsatellite stable(MsS)/mismatch repair-proficient(pMMR)tumors is an attractive,but debatable *** phase 2,multicenter,prospective,single-arm study enrolled patients from 6 centers from June 2021 to November *** advanced rectal cancer(LARC,cT_(3-4a)N_(0)M_(0) and cT_(1-4a)N_(1-2)M_(0))patients aged≥18 years with the distance from distal border of tumor to anal verge≤10 cm(identified by Magnetic Resonance Imaging)were qualifed for *** patients received long-course radiotherapy(50 Gy/25 fractions,2 Gy/fraction,5 days/week)and three 21-day cycles capecitabine(850-1000 mg/m2,bid,po,day1-14)and three 21-day cycles tislelizumab(200 mg,***,day8)as *** mesorectal excision(TME)was 6-12 weeks after the end of radiotherapy to achieve radical resection.A total of 50 patients were enrolled in this *** pathological complete response rate was 40.0%[20/50,95%confidence interval(CI):27.61-53.82%],while 15(30.0%,95%CI:19.1-43.75%),9(18.0%,95%CI:9.77-30.8%),2(4.0%,95%CI:1.10-13.46%)patients respectively achieved grade 1,2,and 3 tumor ***-related adverse events(TRAEs)occurred in 28(56.0%)LARC patients,including 26(52.0%)with grade I-II and 2(4.0%)with grade II(1 with grade 3 immune-related colitis and 1 with grade 3 rash).PD-1 blockade plus long-course chemoradiotherapy(CRT)showed promising therapeutic effects according to pathological complete response rate and is well-tolerated in LARC patients.A larger randomized controlled study is desired to further validate the above findings.

关键词： rectal cancer phase